The inventive concept is related to semiconductor memories, and more particularly, to an operation method of a memory controller and a nonvolatile memory system including the memory controller.
A semiconductor memory device is a memory device which is fabricated using semiconductors such as silicon (Si), germanium (Ge), gallium arsenide (GaAs), indium phosphide (InP), and the like. Semiconductor memory devices may be classified into volatile memory devices and nonvolatile memory devices.
The volatile memory devices may lose stored contents at power-off. The volatile memory devices include a Static RAM (SRAM), a Dynamic RAM (DRAM), a Synchronous DRAM (SDRAM), etc. In contrast, the nonvolatile memory devices may retain stored contents even at power-off. The nonvolatile memory devices include, for example, a Read Only Memory (ROM), a Programmable ROM (PROM), an Electrically Programmable ROM (EPROM), an Electrically Erasable and Programmable ROM (EEPROM), a flash memory device, a Phase-change RAM (PRAM), a Magnetic RAM (MRAM), a Resistive RAM (RRAM), a Ferroelectric RAM (FRAM), etc.
A flash memory is being used in various fields because of low power consumption, a low noise, a large capacity, etc. As flash memory devices having large capacity are used in various fields, various security technologies with respect to a flash memory are being developed. For example, encryption technologies such as an FDE (full disk encryption) of encrypting a drive based on encryption software, and an SED (self encryption drive) when a drive performs an encryption for itself, are being provided.
The SED not only performs an encryption and a decoding but also supports a pre-boot authentication for itself. When a host connected to an SED is booted or the SED is linked-up to the host, the host loads a pre-boot area instead of loading a user area of the SED to perform a pre-boot authentication operation. Since the host can access the user area of the SED only when the pre-boot authentication is succeeded, the user area is protected. A function for the authentication operation described above is provided on the basis of a shadow MBR (shadow-master boot record). In the case of an update of the shadow MBR, since the host cannot recognize the shadow MBR, a separate update or a management method may be required.